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O:U and E:I Ir verbs will only change from o – u Ir verbs will only change from o – u And e – i And e – i

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REGLAS Only Ir verbs stem change in preterite Only Ir verbs stem change in preterite Only in 3 rd singular and 3 rd plural Only in 3 rd singular and 3 rd plural Only from o-u; and e-i Only from o-u; and e-i